Gap · Waterproof Sports & Performance Undergarments
Old Navy Men's Go-Dry Cool Performance Boxer Briefs
Lower concern; no water repellency treatment claimed or disclosed.
Performance boxer briefs with synthetic moisture-wicking fabric. No waterproofing, stain resistance, or water-repellent coating treatment mentioned, reducing typical PFAS risk from athletic wear. Brand silent on PFAS; verify fabric sourcing if concerned.
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Material
polyester/nylon blend performance fabric
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
Safe base material
Made from a material with no inherent PFAS use (ceramic, mineral, or natural fiber).
Category baseline
clothing is a category where PFAS exposure is more common.
No PFAS disclosure
No public statement about PFAS in this product.
The full breakdown
What it's made of and why it matters
Go-Dry Cool Boxer Briefs are a polyester/nylon blend engineered for moisture-wicking and quick-dry performance, typical of activewear fabrics. These synthetics are inherently non-toxic in their base polymer form, but the finishing process (dyes, antimicrobial treatments, elastic components) introduces the primary concern window. The absence of any stated water-repellent or stain-guard coating is a safety advantage, as it rules out common PFAS water-repellency treatments found in premium performance wear.
The brand's record and disclosure
Gap Inc. maintains a sustainability website but has not published detailed chemical inventory or restricted substance lists specific to standard apparel lines like Old Navy basics. The brand has faced scrutiny over fast-fashion supply-chain practices but no major chemical hazard recalls have been documented for Old Navy basics in recent years. Disclosure on antimicrobial or flame-retardant finishes is not prominent; this silence is typical for budget activewear but means you cannot verify which production methods or additives were used.
How it compares in its category
Budget performance underwear (Old Navy, Target, Walmart lines) typically relies on low-cost polyester-nylon blends with minimal finishing versus premium brands like Lululemon or Patagonia, which publish chemical restrictions and certifications. Old Navy's Go-Dry line occupies the middle: affordable enough to replace frequently (reducing cumulative chemical exposure) but not certified organic or bluesign-compliant. Compared to cotton boxer briefs, synthetics eliminate moisture-rot risk but carry dye and synthetic polymer finish concerns; the trade-off is neutral from a hazard standpoint if washed properly.
If you buy it
Wash in cool water before first wear to rinse loose dyes and finishes; warm water is safe for routine laundering and does not degrade polyester-nylon at normal temperatures. Avoid fabric softeners and bleach, which can degrade elastic and coating integrity over time. Replace after 50-80 washes or when elastic loses recovery, as degraded elastic may shed microfibers more readily. Do not expose to direct high heat (dryer on high, iron) as nylon can melt; air dry or low-heat tumble dry.
Beyond PFAS: other things we checked
Established hazard classes for this product type, assessed from public information. These never change the PFAS grade; a Likely flag caps the Verdict at “Buy with care.”
Azo dyes and synthetic colorants
Polyester fabrics in budget activewear typically use azo dyes; Old Navy does not disclose dye chemistry or heavy metal content in dyes. Pre-wash rinsing can reduce loose dye migration, but risk of dermal sensitization exists in sensitive individuals.
Antimicrobial finishes (unspecified)
Go-Dry moisture-wicking claims suggest antimicrobial treatment, but Old Navy does not disclose whether silver nanoparticles, triclosan, or other agents are used. Such finishes may leach during wash; composition is not publicly available.
Microplastic shedding
Polyester-nylon blends are documented to shed microfibers during washing. Old Navy products have not been specifically tested, but the material class is known to contribute to laundry water microplastic loads; use a microfiber-catching wash bag to reduce shedding.
Elastic and trim heavy metals
Elastic cores and metal fasteners in underwear can contain nickel or cadmium; no recalls or testing data specific to Old Navy Go-Dry have been published, but direct skin contact warrants pre-wash and monitoring for irritation.
Formaldehyde in fabric finishing
Polyester wrinkle-resistance and durable-press finishes sometimes use formaldehyde resins; Old Navy does not disclose use. Off-gassing risk is low post-manufacturing but pre-wash is prudent for sensitive individuals.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 62% confidence. It is not a lab result.
No independent PFAS lab test is on record for this exact product. A lab test could move the score in either direction.
The brand has not made a specific, verifiable PFAS-free statement, so part of this score reflects that missing disclosure rather than a confirmed material.
Formulations and coatings change between production runs. Always check the current label before buying.
More waterproof sports & performance undergarments grades
How we score: every product runs through the same public 0–100 rubric based on materials, coatings, brand disclosure, lab findings, and recalls. See the full methodology → Spotted a mistake? Report an error.